Push-on/screw-off cap assembly

ABSTRACT

A push-on pull-off and screw-on screw-off closure assembly  20  is provided comprising a spout  30  adapted to be attached to a container  10,  the spout  30  having a wall  36  defining a flow path and having an outer surface  40  having a spiral-shaped spout thread  44  thereon. The assembly also comprises a cap  50  having a base  52  with an outer annular wall  54  extending from the base  52  having an inner surface  58.  The inner surface  58  having a cap thread  60  thereon, wherein the cap thread  60  substantially engages the spout thread  44  and the cap  50  and spout  30  are adapted to close the flow path when the cap  50  is pushed onto the spout  30.

TECHNICAL FIELD

[0001] The present invention relates to a closure assembly for a container and, more particularly, to a cap assembly that can be pushed on or pulled off, or screwed on or screwed off the container spout.

BACKGROUND OF THE INVENTION

[0002] Containers such as collapsible plastic bags are often used to store liquid products such as chemicals, soft drink syrup, fruit juices and food condiments. The plastic bags are typically housed in a corrugated paperboard box to aid in the transporting, handling and dispensing of the product. The paperboard box provides structural support to the flexible plastic bag filled with liquid product. Such packaging systems are commonly referred to as “bag-in-box” packaging systems.

[0003] The plastic bags typically have sidewalls sealed along a peripheral seam to define a fluid containing chamber. A spout or a fitment provides access to the fluid chamber for filling and dispensing the product within the bag. A closure assembly is provided in the form of a cap assembly that fits over the spout to close the plastic bag. Vacuum pump systems are sometimes connected to the spout to assist in draining fluid from the bag.

[0004] The bag-in-box assemblies are typically filled by a filler at a plant location using an automated filler apparatus. The filler apparatus is designed to utilize a friction-fit or interference-fit cap that is pulled-off the container spout just before product is injected into the container. The cap is then pushed back onto the spout after filling forming an interference fit between the cap and spout to therefore close the container. The filler apparatus is not available in a configuration to manipulate a screw-on/screw-off cap assembly because this type of configuration would slow down the filling process. In addition, a threaded cap/spout assembly would add complexity to the container. Certain container applications cannot accommodate this cap complexity. For example, sometimes the bag-in-box assemblies require aseptic filling wherein the cap/spout define an aseptic zone that must be kept free from contamination. A complex screw mechanism in this application is unacceptable as it would be impractical to keep the cap and spout clean and sterile.

[0005] The end user of the bag-in-box assembly, however, often desires a screw-on/screw-off cap so it can screw-off the cap and screw onto the spout a pump assembly to dispense the liquid from the container. This is true even for end users utilizing the bag-in-box assemblies in aseptic processes. Thus, it is desirable to have a cap for the plastic bags that can be pulled-off and pushed-on by the filler but can be screwed off and on by the end user.

[0006] The present invention is provided to solve these and other problems.

SUMMARY OF THE INVENTION

[0007] The present invention provides a closure assembly for a container. The closure assembly comprises a cap assembly that is adapted to be pulled-off and pushed-on a container spout assembly during a filling process and screwed-off, or twisted-off, and screwed-on or twisted-on for removal from and attachment to the container spout by an end user.

[0008] According to one aspect of the present invention, a closure assembly is provided. The assembly comprises a spout adapted to be attached to a container. The spout has a cylindrical wall defining a flow path and an outer surface having a spiral-shaped spout thread thereon. The assembly further comprises a cap having a base, an outer annular wall extending from the base having an inner surface, and the inner surface having a cap thread thereon, wherein the cap thread is adapted to substantially engage the spout thread and the cap and spout are adapted to seal the flow path when the cap is pushed onto the spout.

[0009] Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which:

[0011]FIG. 1 is an isometric view of a flexible container with the closure assembly of the present invention attached thereto;

[0012]FIG. 2 is an isometric exploded view of a closure assembly of the present invention with a portion of the cap shown in phantom;

[0013]FIG. 3 is a top plan view of a closure assembly of the present invention in an assembled state;

[0014]FIG. 4 is an isometric view of the cap of FIG. 3;

[0015]FIG. 5 is a top plan view of the cap of FIG. 4;

[0016]FIG. 6 is a side sectional view taken along the line 6-6 of FIG. 5;

[0017]FIG. 7 is an isometric view of the spout of FIG. 2;

[0018]FIG. 8 is a top plan view of the spout of FIG. 7;

[0019]FIG. 9 is a side sectional view of the spout taken along the line 9-9 shown in FIG. 8;

[0020]FIG. 10 is a side elevation section of the closure assembly taken along the line 10-10 as shown in FIG. 3;

[0021]FIG. 11 is a side elevation section of the closure assembly taken along the line 11-11 as shown in FIG. 3;

[0022]FIG. 12 is a side elevation section of the closure assembly taken along the line 12-12 as shown in FIG. 3;

[0023]FIG. 13 is a side elevation section of the closure assembly taken along the line 13-13 as shown in FIG. 3; and

[0024]FIG. 14 is a top plan view of the assembled closure assembly of the present invention wherein the cap has been rotated in a counterclockwise position from that shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0025] While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.

[0026] Referring now in detail to the Figures, FIG. 1 shows a flexible container generally designated with the reference numeral 10. The container can be any type of container. In one preferred embodiment the container 10 is flexible collapsible bag used to store liquid products. Attached to the flexible container 10 is a closure assembly 20 of the present invention. As can be seen in FIG. 2, the closure assembly 20 includes a spout or spout assembly 30 and a cap or cap assembly 50.

[0027] FIGS. 7-9 generally depict the spout assembly 30. The spout 30 has a cylindrical wall 36 with a flange 32 at a base end 34 thereof. The flange 32 facilitates attachment of the spout 30 to the container 10, said attachment generally shown in FIG. 1. The cylindrical wall 36 defines a flow path in line with the axis X. The cylindrical wall 36 has an outer spout surface 40 and an inner spout surface 42. A top end 38 of the cylindrical wall 36 is generally sized and adapted to be received by the cap 50. Near the vicinity of the top end 38, a spout-thread 44 is located on the outer spout surface 40. The spout-thread 44 extends for approximately one full revolution of the spout 30 or for approximately 360 degrees. The spout-thread 44 has an upper spout thread surface 45. The spout thread 44 also has spout thread beginning point 31 and a spout thread ending point 33.

[0028] Also located on the outer spout surface 40 is an outer spout ring or annular spout protrusion 46. The outer spout ring 46 is depicted in the FIGS. as being located at the top end 38 of the cylindrical wall 36. The outer spout ring 46 has a ring height 47 in the direction of axis X. An inner annular seal ring or annular spout projection 48 projects from the inner spout surface 42.

[0029] Located on the outer spout surface 40 and extending radially therefrom is an intermediate flange or handling ring 49. The handling ring 49 is located between the flanged base 32 and the spout thread 44. The handling ring 49 facilitates the handling of the spout by an automated filler (not shown).

[0030] Referring to FIGS. 4-6, the cap 50 has a base 52, an outer annular wall or thread skirt 54 and an inner annular wall or plug ring 64. The base 52 has a locator or orienting notch 53. The base also has a series of gripping grooves 51 about its periphery.

[0031] The thread skirt 54 has an outer surface 56 and an inner surface 58. The thread skirt 54 has an end surface 55 distal from the cap base 52. The thread skirt 54 extends generally perpendicularly from the base 52. However, as presently preferred and shown in FIG. 6, the thread skirt extends from the base 52 such that a diameter of the thread skirt 54 near the base 52, is smaller than a diameter of the thread skirt 54 near the end surface 55.

[0032] Extending from the inner surface 58 of the thread skirt 54 is a single helical or spiral cap-thread 60. The cap-thread 60 has an upper cap thread surface 61 and a lower cap thread surface 62. Both the upper cap thread surface 61 and the lower cap thread surface 62 are at approximately a 45 degree angle to the thread skirt inner surface 58. The cap-thread 60 extends approximately 360 degrees about the inner surface 58 of the thread skirt 54. The cap thread 60 has a cap thread beginning point 72 and a cap thread ending point 74. The cap-thread 60 both begins and ends in the vicinity of the orienting notch 54.

[0033] A recess or annular groove 63 is located on the inner surface 58 of the thread skirt 54. The annular groove 63 is positioned between the cap thread 60 and the base 52. The annular groove 63 has a groove height 65 with an upper surface 67 and lower surface 69. The groove height 65 is greater than the ring height 47.

[0034] The plug ring 64 extends from the base generally perpendicularly and has an outer sealing surface 66 and a plug ring end surface 68. As shown in FIG. 6, the intersection of the outer sealing surface 66 and the end surface 68 is rounded off to form a rounded guide surface or edge 70.

[0035] In operation, the cap 60 may be affixed to the spout 30 by pushing it or snapping it onto the spout 30. To push the cap 60 onto the spout 30, the cap 60 must first be properly oriented with respect to the spout 30. The cap 60 should be positioned such that the thread skirt 54 is extending from the base 52 towards the spout 60 in a manner to receive the top end 38 of the cylindrical wall 36, as can be seen in FIG. 2. Also, the cap 60 must be rotationally oriented with respect to the spout 30 prior to being pushed onto the spout 30. The orienting notch 53 on the cap 60 must be oriented to coincide with a starting position on the spout 30. The starting position of the spout 30 will be that point along its outer surface 40 that substantially simultaneously allows the cap thread beginning point 72 to pass over the spout thread 44; allows the outer sealing surface 66 of the plug ring 64 to form an effective seal with the inner seal ring 48; and allows the outer spout ring 46 to be received by the annular groove 63 forming an interference fit; as the cap 50 is pushed onto the spout 30. In one preferred embodiment shown in the figures and described herein, the starting position is located approximately 90 degrees counterclockwise from that point on the cylindrical wall 36 where the spout thread 44 begins and ends. Although not shown in the FIGS., it is understood that a starting point indicator or marker may be included on the spout to identify the starting point.

[0036] Once this particular orientation of the cap 50 and spout 30 is achieved, the cap 60 may be pushed or snapped onto the spout 30 through the application of a force to the cap 60 generally perpendicular to the base 52 and in the direction of the spout 30.

[0037] As the cap 60 initially moves towards the spout 30 in this orientation, the rounded guide surface 70 assists in the mating of the plug ring 64 with the cylindrical wall 36 and in positioning the cap 60. Also, as the cap thread 60 and the spout thread 44 are of the same or a matching pitch, a substantial portion of the cap thread lower surface 62 comes into contact with a substantial portion of the spout thread upper surface 45. Because the cap thread lower surface 62 and the spout thread upper surface 45 are at roughly a forty five degree angle to the line of force being applied, a radial force is exerted on the cap thread 60. Because the thread skirt 54 is made from a material to be sufficiently resilient, the thread skirt 54 deflects outward and allows the cap thread 60 to pass over the spout thread 44.

[0038] Once the cap thread 60 has passed over the spout thread 44, the outer sealing surface 66 of the plug ring 64 frictionally engages the inner seal ring 48 of the cylindrical wall 36, forming a seal and closing off the flow path through the spout 30. Also, the outer annular spout ring 46 cooperates with the annular groove 63 to form an interference fit that holds and maintain the cap 50 on the spout 30. In this initial orientation of the cap 50 and spout 30, the spout ring 46 is adjacent the upper surface 67 of the annular groove 63.

[0039] Referring to FIGS. 10-14, when the cap 50 and spout 30 are in the assembled state shown therein, an annular space is formed between thread skirt inner surface 58 and the outer spout surface 40. An annular passage is formed by the end surface 55 of the thread skirt 54 and the handling ring 49. The annular passage is in flow communication with the annular space. This allows a steam sterilization solution to be utilized to sterilize inner surface 58 and outer spout surface 40, after the cap 50 has been pushed on or screwed on to the spout 30.

[0040] The cap 50 can also be pulled off of the spout 30 by applying a sufficient force perpendicular to the base 52 and away from the spout 30. Similar to pushing the cap 50 onto the spout 30, in pulling it off, a radial force is exerted between the spout thread 44 and the cap thread 60. This causes the thread skirt 54 to deflect outward and allows the cap thread 60 to pass over the spout thread 44. At substantially the same time, the interference fit between the annular groove 63 and the outer spout ring 46 is over come and the plug ring outer sealing surface 66 frictionally disengages the inner seal ring 48 to open the flow path through the spout 30.

[0041] The cap 50 can also be screwed off the spout 30. To remove the cap 50 from the spout 30 in this way, one merely needs to rotate the cap 50 in a counterclockwise direction relative to the spout 30. In doing so, the lower cap thread surface 62 cooperates with the upper spout thread surface 45 to create an axial force tending to separate the cap 50 from the spout 30.

[0042] Subsequent to the initial rotation, an intermediate orientation is reached as depicted in FIG. 14. In this intermediate position, the outer spout ring 46 abuts the lower surface 69 of the annular groove 63. Continued rotation of the cap 50 results in the axial force becoming greater than that required to break or overcome the interference fit between the outer annular spout ring 46 and the annular groove 63. As this interference fit is being overcome, the outer sealing surface 66 of the plug ring 64 separates or frictionally disengages from the inner seal ring 48 breaking the seal created therebetween and opening the flow path through the spout 30. The thread skirt 54 is sufficiently rigid to prevent the cap thread 60 from passing over the spout thread 44 while rotating the cap relative to the base. In one preferred embodiment depicted in the figures, a rotation of the cap 50 of approximately 270 degrees from the initial orientation is required to separate the cap 50 from the spout 30. However, the amount of required rotation may be varied depending upon the configuration and pitch of the particular threads and the configuration of the interference or friction fitting used in any particular embodiment.

[0043] The cap 50 may also be screwed onto the spout 30. In doing so, one would move the cap 50 towards the spout 30 such that the spout 30 begins to be received by the thread skirt 54. The cap 50 is then rotated in a clockwise direction as looking at the assembly from the perspective shown in FIG. 3. In doing so, the cap thread 60 will begin to engage the spout thread 44, both of which will generally cooperate to advance the cap 50 towards the spout 30. As the cap 50 so advances, the annular groove 63 receives the outer spout ring 46 forming an interference fit holding the cap 50 on the spout 30, and the inner seal ring 48 frictionally engages the outer sealing surface 66 of the plug ring 64, sealing the flow path through the spout 30.

[0044] While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying Claims. 

We claim:
 1. A closure assembly comprising: a spout adapted to be attached to a container, the spout defining a flow path and having an outer surface, the outer surface having a spiral-shaped spout thread thereon, the spout thread having an upper surface; a cap having a base, an outer annular wall extending from the base having an inner surface and a cap thread located on the inner surface; wherein a substantial portion of the cap thread engages the spout thread and the cap is adapted to seal the flow path when the cap is pushed onto the spout.
 2. The closure assembly of claim 1 wherein the cap thread and the spout thread have the same pitch.
 3. The closure assembly of claim 1 further comprising: an annular space between the thread skirt and the spout; an annular passage in flow communication with the annular space; wherein the annular passage permits a steam sterilization composition access to the annular space.
 4. The closure assembly of claim 3 further comprising: an end surface on the thread skirt; a handling ring from the outer surface of the spout; wherein the annular passage is defined by the intermediate flange and the end surface.
 5. The closure assembly of claim 1 further comprising: an annular groove located on the inner surface of the outer annular wall of the cap; an annular spout protrusion extending from the spout outer surface; wherein the annular groove and the spout protrusion cooperate to form an interference fit when the cap is pushed onto the spout.
 6. The closure assembly of claim 5 wherein the cap thread and spout thread cooperate to overcome the interference fit and un-seal the flow path when the cap is rotated relative to the spout.
 7. The closure assembly of claim 1 further comprising: an inner annular wall extending from the base having an outer surface, the inner annular wall being circumjacent to the outer annular wall; wherein the outer surface of the inner annular wall of the cap frictionally engages an inner surface of the spout when the cap is pushed on the spout.
 8. The closure assembly of claim 7 wherein an inner seal ring extends from the inner surface of the spout wall and the outer surface of the inner annular wall of the cap frictionally engages the inner seal ring.
 9. The closure of claim 8 wherein the cap thread and the spout thread cooperate to frictionally disengage the outer surface of the inner annular wall of the cap from the inner seal ring when the cap is rotated relative to the base.
 10. The closure assembly of claim 1 wherein the outer annular wall is sufficiently resilient to allow the cap threads to pass over the spout threads when the cap is pushed onto the spout and sufficiently rigid to permit the spout thread and the cap thread to cooperate to separate the cap from the spout when the cap is rotated relative to the spout.
 11. The closure assembly of claim 1 wherein the spout thread and cap thread cooperate to separate the cap from the spout when the cap is rotated relative to the spout.
 12. The closure assembly of claim 11 wherein the cap is rotated in a counterclockwise direction relative to the spout.
 13. The closure assembly of claim 11 wherein the cap is separated from the spout when the cap is rotated approximately 270 degrees relative to the spout.
 14. The closure assembly of claim 1 wherein: the spout has a top end; the spout thread has a beginning point and an end point and extends about the outer surface of the spout for approximately 360 degrees, the spout thread beginning point being distal from the top end of the spout as compared to the spout thread ending point; the cap thread has a beginning point and an end point and extends about the inner surface of the thread skirt for approximately 360 degrees, the cap thread beginning point being distal from the base as compared to the cap thread end point; the cap having a thread indicator thereon in the vicinity of the cap thread beginning point; a starting location on the outer surface of the cylindrical wall; wherein when the thread indicator is rotationally aligned with the starting point, the cap thread beginning point passes over the spout thread and the cap seals the flow path as the cap is pushed onto the spout.
 15. The closure assembly of claim 14 wherein the starting location is at a point on the spout outer surface anywhere between approximately 90 degrees and approximately 270 degrees from the spout thread beginning point.
 16. The closure assembly of claim 15 wherein the starting location is at a point along the outer surface of the spout approximately 90 degrees from the spout thread beginning point.
 17. The closure assembly of claim 15 wherein the starting location is at a point along the outer surface of the spout approximately 90 degrees counterclockwise from the spout thread beginning point.
 18. A closure assembly comprising: a spout adapted to be attached to a container, the spout having an outer surface and inner surface, the outer surface having a spiral-shaped spout thread thereon and an annular spout protrusion extending therefrom, the inner surface having an annular spout projection extending therefrom; a cap having a base, an outer annular wall extending from the base with an inner surface having a cap thread thereon, the inner surface further having an annular groove, an annular wall extending from the base having an outer surface and being circumjacent to the outer annular wall; wherein, when the cap is pushed onto the spout, the outer annular wall is adapted to allow the cap thread to pass over the spout thread, the annular groove receives the annular spout protrusion, and the outer surface of the inner annular wall frictionally engages the annular spout projection, and when the cap is rotated relative to the base, the cap thread and the spout thread cooperate to separate the cap from the spout.
 19. A flexible container assembly comprising: an internal chamber for containing a liquid product; a spout attached to the container and in flow communication with the internal chamber, the spout having an outer surface with a spiral-shaped spout thread thereon; a cap having a base, an outer annular wall extending from the base with an inner surface having a cap thread thereon; wherein the cap thread substantially engages the spout thread and the cap and spout cooperate to seal the spout when the cap is pushed onto the spout.
 20. The flexible container assembly of claim 19 further comprising: an annular groove located on the inner surface of the outer annular wall; an inner annular wall extending from the base having an outer surface, the inner annular wall being circumjacent to the outer annular wall; the spout inner surface having an annular spout projection extending therefrom, the spout outer surface having an annular spout protrusion extending therefrom; wherein the outer surface of the inner annular wall frictionally engages the annular projection and the annular groove receives the spout protrusion.
 21. A cap assembly for sealing a spout having an outer surface and an inner surface, the outer surface having a spiral-shaped spout thread, the cap assembly comprising: a base; an outer annular wall extending from the base having an inner surface with a spiral shaped cap thread thereon; wherein the cap thread substantially engages the spout thread and the cap assembly is adapted seal the spout when the cap assembly is pushed onto the spout.
 22. The cap assembly of claim 21 further comprising an inner annular wall extending from the base, the inner annular wall having a sealing surface, the sealing surface being adapted to frictionally engage the inner surface of the spout.
 23. The cap assembly of claim 21 further comprising an annular groove located on the inner surface of the outer cylindrical wall wherein the annular groove is adapted to form an interference fit with an annular spout protrusion located on the outer surface of the spout.
 24. A closure for a container, the closure comprising: a spout adapted to be attached to the container, the spout having an inner surface and an outer surface, the spout inner surface having a having a projection extending therefrom, the outer wall having a spiral-shaped thread thereon, the thread having an upper surface; a cap having a base, an inner wall extending from the base and an outer wall extending from the base, the inner wall being circumjacent to the outer wall, the inner wall having a recess that receives the projection when the cap is pushed onto the spout, the outer wall having an inner surface with a cap thread thereon, the cap thread engaging the upper surface of the spout thread
 25. A cap assembly for a flexible container, the container having an internal chamber for containing a liquid product, the cap assembly comprising: a spout adapted to be attached to the container and in fluid communication with the internal chamber, the spout having a spout thread and an outer spout ring on an outer surface of the spout; a cap having a base, a thread skirt extending from the base having an inner surface, a cap thread on the inner surface of the thread skirt, and an annular groove on the inner surface of the thread skirt; wherein the cap can be pulled-off and pushed onto the spout and screwed-off and screwed onto the spout. 